A large part of the appeal of food products which are deep-fried or likewise prepared comes from the characteristic crispness of the exterior of the products, while the interior of the products is typically hot and moist. These characteristics are particularly appealing in such foods as French fried potatoes, hash brown potatoes, batter-fried chicken nuggets, and other similar fried foods. When properly prepared, these types of food have an appealingly crisp surface texture, while the interior of the products is moist and tender.
In the food service industry, preparation and service of fried food products having the desired sensory characteristics can be difficult. Although deep-frying and like cooking techniques can be suitably refined to provide fried products having the desired characteristics upon completion of cooking, problems are generally encountered in maintaining the desired surface crispness of the products between the time they are cooked and the time they are served. It is generally recognized that the crispness of fried foods is adversely affected within a relatively short time after they are cooked because moisture from within the interior of the products migrates to their surfaces. Consequently, the surfaces of the products lose their desired cripness, this condition being readily detectable when the products are consumed since they tend to feel soggy and/or greasy, and may taste of the frying medium.
In the fast service restaurant industry, a premium is placed upon quick and efficient service of food, and this essentially precludes individual cooking of each food order. In view of this, concerted efforts have been made to perfect arrangements for holding fried food products after they are cooked, but before they are served, to preserve their desired crispness and sensory appeal.
In the past, the most commonly employed methods for attempting to maintain the desired characteristics of freshly fried food products has been to position infra-red emitting heat lamps in close proximity to the products or to place products in heated holding cabinets, such as those having doors or drawers. Enclosed cabinets make the product relatively less accessible. The infra-red devices produce infra red radiation emitted from incandescent or quartz lamps which radiation strikes the food products in the associated holding area to aid in the retention of heat in the products. While these methods for holding fried food prior to service are very widely used, experience has shown that freshly fried food products can only be maintained for a limited period of time before the sensory appeal and characteristic crispness deteriorate significantly. This primarily results from the migration of moisture from the interior of the products to the exterior, with a heat source such as the infra-red radiation striking the products only tending to keep the products warm, but not crisp. As a consequence, the preparation of fried food products must be very carefully coordinated with customer demand at any given time. In the event that fried foods are not sold within a relatively short time after they are cooked, they can only be served at the risk of great customer dissatisfaction, and therefore should be discarded.
In view of the desirability of maintaining the sensory quality of fried food products for as long as possible after they are fried, the introduction of a method and apparatus for maintaining the crispness of fried food products represents a significant development, particularly for the fast service restaurant industry, in view of the enhanced product quality and flexibility in product preparation attainable.